Rotary underreamer



April 23, 1929. G. F. LE Bus ROTARY UNDERREAMER Filed May 3, 1927 w my 25 VI 2 W m. 9

ATTORNEYS Patented Apr. 23, 1929.

unease anoaen 1'. LE BUS, on ELECTRA, TEXAS.

ROTARY UNDERREAMER.

Application filed May 3, 1927. Serial No. 188,489.

a This invention relates'to rotary underreamers. v

An obj eet of the invention is the provision of a reamer whiclrhas apositive action for forcing cutting blades into the wall so that whenthe device is rotated the wall of the .hole will be increased in size,the increase depending upon the size of the cutting blades with whichthe tool is equipped.

provision of a rotary underreamer for increasing the diameter of'a wellafter the usual reamer increases the depth of the wall, the action ofcutting the hole to an increased the reamer which increases the depth.

A still further object of the invention is the provision of a reamer inwhich no springs are employed and in which the cutting blades are forcedinto operative position by a force acting longitudinally of the tool sothat the action is positive when the blades are predeterminedly forcedinto position. T

This invention will be best understood from a consideration. of thefollowing detailed description, in view of the accompanying drawingsforming a part of the specification; nevertheless it is to be understoodthat the invention is not confined to the disclosure, being susceptibleof such changes and modifications which shall define no materialdeparture from the salient features of the inventidn as expressed in theappended claims.

Figure 1 is'a vertical section of my improved reaming tool showing theblades in an inoperative position.

Figure 2 is a similar vertical section showing the blades moved to anoperative cutting position.

Figure 3 is a fragmentary view in perspective showing the cutting bladesin operative relation with the body of the tool. Referring moreparticularly to the drawings, designates the main body section -which isthreaded at 11 for connecting the same to the usual-working parts whichoper- V ates the reamer, the body member has an axial passage 12 runninglongitudinally of the entire body.

size, being simultaneous with the advance within slots 31 in that Atubular body member 13 is provided with slots 14 in which are mounteddogs 15, pivoted at 16. These dogs are maintained in extended relationfrom the body member 13. The dogs are bowed as shown at. 17 to provideeffective engaging sections 18 which make frictional contact with thewall of the hole .or the pipe in order to cause the body member whichhas a threaded engagement A further object of the invention is the at 19with the main body 10 to be forced downwardly for a purpose which willbe presently described.

The lower end of the member 13 has an' internal chamber of greaterdiameter than the upper portion and is threaded at20 to receive thethreads of the tubular sleeve 21 which slides on the main body 10. Asecond sleeve 21 at its inner end has an annular rib 22'adapted toengage a nut 23 which is screwed into the upper end of-a sleeve 24, thissleeve being spaced as shown at 25 from the main body 10, but in contactwith. the main body at its lower end. The extreme inner end as shown at26 is curved to provide an annular cam to engage the curved portions 27of cutter blades 28.

The cutter blades may be any number and are normally seated within slots29 in the enlarged portion 30 of the body member 10 when thetool isbeing withdrawn from the well. However, when the tool is forced into thewell preparatory to increasing the diameter of the well these blades arereceived portion of the body member which is directly above the enlargedportion 30 otsaid body member. The slots 31 curve outwardly at theirupper ends as shown at 32 to neatly receive the. curved portions 27adjacent the cutting edges of the blades.

The lower end of the body member is provided with an internal flangedrecess 33 into which is secured the shank 34 of a reamer 35 which isadapted to cut the hole in the ground and increase the depth of thewell. The nut 36 is secured on to the threaded shank 34 of the reamer35. of the reamer is provided with expanded cutting edges 37 and has aslot38 opening. into thepassage 12 in the body 10 so that water may beforced downwardly through The lower end.

I through their eifective' portions 18 will enthe casing and gage withthe casing or the wall of the hole and maintain the sleeve or body 13against rotation, whereby the body member 13' is substantially screweddownwardly to carry the sleeve 21 downwardlyand permitting the weight orsleeve, 26 to move downwardly against the curved portion 27 of theblades 28. When this action occurs said blades will be forced downwardlyto their hori- .zontal positions as shown in Figure 2 and the tool isnow ready for reaming the walls of the well to an.increased size.

After the desired reaming has been done the tool is raised and thecutters collapse or move downwardly because of their frictionalcontact-with the wall of the well and seat within the pockets 29. Thisaction of the blades permits the tool to be readily withdrawn-from thewell.

It will be seen by such a construction that this tool may be employed-inthe process of rotary drilling and is so constructed that it may readilybem'oved downwardly .through enlarge the hole in the sand, therebyincreasing the production of the well. This toolalso may be employed'inproducing wells where the sand has become.

parafiined which closes off the oil. This tool may also be run on. thetubing to remove the parafiin from the walls of the sand thus increasingthe production of old wells.

The inconvenience of the other methods of rotary drilling is the factthat when the casing has been set on the sand and the sand drilled inthe usual way, the passage in the sand is substantially the same size asthe casing.

As the body 10 is rotated and screwed into the threads of the sleeve 13.the dogs 15 will engage the walls of the well and prevent rotation ofsaid sleeve. At this time the weight 2t descends forcing the cutters orblades-28 outwardly from the body member.

When the member 22 is moved downwardly and engages the shoulder of thepocket 25, at the inner end of the pocket, and further when the lowerend of the threads of the sleeve 13 reach the terminus at the lower endof the threads on the body 10, the member 10 and sleeve 13 can not bescrewed any further and they will be locked against independentrotation. At this time, the blades 28 have been moved out to theposition shown in Fig. 2. The resistance of the dogs 15 against therotation of the sleeve 13 will be sufficient to maintain the sleeveagainst .rotation during the positioning of the blades 28. However, whenthe blades are in the position shown in Fig. 2,,and the sleeve 13 hasbeen screwed to its longitudinal limit of movement with respect to thebody member 10, the continued rotation of the body -mcmber '10 willcause rotation of the sleeve 13 and likewise the cutters 28. It will beappreciated that the resistance of the dogs 15 will only be suflicientto maintain the sleeve against movement during the positioning of theblade 28.

I claim 1. A reamer comprisinga body member, a

sleeve having a threaded engagement with the body member, means formaintaining the sleeve in frictional contact with the walls of an oilwell, a second sleeve having a threaded engagement with the firstmentioned sleeve, a weighted sleeve loosely supported by the secondmentioned sleeve and adapted to move downwardly on the body member whenthe said second mentioned sleeve is moved downwardly on said bodymember, said body member being provided with pockets, blades adapted tobe neatly seated within the pockets and having their free ends engagedby the inner end of the weighted sleeve, and a reamer secured to theinner end of the body member.

2. A reamer comprising a body member having a longitudinal passagetherethrough, a sleeve having threaded engagement with the body member,said sleeve being provided with recesses, spring pressed dogs mounted inthe recesses, a second sleeve having a threaded engagement with thefirst mentioned sleeve and provided with an annular rib at its innerend, and a third sleeve movable relative to the second mentioned sleeve,a nut threaded to the third mentioned sleeve and adapted to rest on therib of the second mentioned sleeve, the third mentioned sleeve beingweighted, said body member having a plurality of pockets, a reamer bladepivotally mounted in each pocket and adapted to be engaged by theweighted sleeve so that when the sleeve is moved inwardly the bladeswould be forced into operative position, and a reamer removably securedto the inner end of the body.

3. A reamer comprising a body member having a longitudinal passagetherethrough, a sleeve having threaded engagement with the body member,said sleeve being provided with recesses, spring pressed dogs'mounted inthe recesses, a second sleeve having a threaded engagement with thefirst mentioned sleeve and provided with an annular rib at its innerend, and a third sleeve movblade pivotally mounted in each pocket andable relative to the second mentioned sleeve, adapted to be engaged bythe weighted a nut threaded on to the third mentioned sleeve-so thatwhen the sleeve is moved in- 10 .sleeve and adapted to rest on the ribof the wardly the blades would be forced into 0psecond mentioned sleeve,the third mentioned erative position. sleeve being weighted, said bodymember having a plurality of pockets, a i'eamer GEORGE F. LE BUS.

